Project Maitai/Mahitahi - three years on

19 June 2017

As Project Maitai/Mahitahi flows into its fourth year, we can celebrate some fantastic achievements, and some exciting projects still to be completed.
Most notably, in late 2016, the Maitai River was named the second Most Improved River in the New Zealand River Awards. This award was based on improvements in macro-invertebrate scores at a key site in the river, and reflects the improvement in river health that Project Maita/Mahitahi is working towards.

The toxic algae and E.coli monitoring results have been encouraging too. The E.coli levels at the Maitai Riverside monitoring site are showing a meaningful trend improvement over time. You can see the results on the LAWA website.

There were no known toxic algae incidents over the summer and toxic algae levels remained below the alert level, no doubt helped by the wetter summer weather. Several Dog’s Breakfast events were held over the summer to raise public awareness and teach dog owners to recognise toxic algae so that they feel comfortable about using the river.

L - Nelson College for Girls students monitoring the Maitai River; R - Dog's Breakfast

Riparian Planting

A well-vegetated streamside is an important part of river ecology. Our fish need cool, well shaded water and vegetation close to the water’s edge (some species actually climb out of the water and lay their eggs amongst streamside grasses).

Trees provide bank stabilisation, and prevent erosion. They drop leaf litter in to the river which provides cover and food for macro-invertebrates, which in turn provide food for fish. Insects and birds thrive in an area rich in forest cover, and tree-lined waterways provide food corridors for birds as well as shade for fish.

The Friends of the Maitai have been restoring an area of native forest near Groom Creek. The first trees planted are now three years old, and work now is focussed on maintenance, chemical-free weed control and releasing trees from the grass. Infill planting takes care of any gaps that open up, and the group is also running a trapping programme. The group has planted over 4000 trees, and regular maintenance sessions are held every other Friday evening.

Several sites along the Maitai River have been planted by Council this year, including around the Maitai Dam to reduce temperatures around the spillway, and in the urban area around Avon Terrace. Plantings have also taken place along the tributary to the Brook, and in the Brook itself, around the Tantragee Reserve. These plantings have been undertaken by school groups and Council and will be the site of a community planting in early spring.
   

Fish Passage Improvements

Our native fish need to be able to migrate up and down rivers to spawn, so their survival depends on our streams being fish-passage-friendly. We’ve made great progress with this over the last year.

In the Maitai River, we’ve removed the two concrete fords that were the main fish barriers. In the Brook Stream, we’ve added cross-current baffles at the Nile Street culvert that break up the strong current and provide a resting place for fish. A new sign at the intersection of Nile and Tasman streets tells the story of the work and the reason it has been done. Cross-current baffles have also been added in the York Stream.

There is more work to do in the Brook, but recently our scientists were excited to find koaro eggs on midstream rocks upstream from the baffles. We also found a threatened lamprey just below the Almond Tree Flat Ford – once the ford was removed it was able to make its way upstream to spawn. These are the first known records of lamprey or koaro eggs in the Maitai catchment.
     

Groom Creek

If you regularly visit the Maitai side of the Tantragee Reserve, you’ll notice trees being planted and weeds being cleared in the Groom Creek area.

Resource Consent has been granted for the construction of Groom Creek wetland and the contract is currently being tendered. Preparation work is well underway, with clearing of weeds and initial planting of the sloping area behind the site of the wetland, which will begin the forest regeneration process.

The wetland will act as a natural filter, reducing the sediment and nutrients from the surrounding forest being washed into the river. It will restore Groom Creek to its natural path, increase biodiversity and improve stream health.

The wetland is on track to be completed over the next year. Once finished this project will be a major legacy for Project Maitai/Mahitahi and an important contributor to the long term wellbeing of the river.

    

York Stream Focus

York Stream is one of the Maitai Catchment streams. It runs through housing and the Bishopdale reserve, and then travels underground for some way before popping up again near the Railway Reserve. Project Maitai/Mahitahi has been working to raise awareness of this waterway, which travels beside houses and beneath roads, and to encourage people to engage with and value ‘their stream.’

To this end, Project Maitai/Mahitahi has worked with a local artist to develop artworks along the stream’s edge at Victory School, and on the Koha Shed above the stream’s subterranean channel at the Victory Community Centre.

There has also been an interactive stall at the Race Unity Day, and at the recent Matariki celebrations at Victory Community Centre. There's a current installation at the Nelson Provincial Museum using water temperature monitors in the stream, connected wirelessly to the display in the museum, showing variations in water temperature and the impact that has on fish life.

Further work will involve the mapping and removal of fish barriers, and work to address E.coli sources in the stream. Many thanks to all the businesses who have sponsored these artworks.

      

The Koha Shed - Victory Community Centre

Urban Water Quality

Our city streams are as much a part of our natural landscape as those in the back country.

Looking after the lower reaches of the Maitai River, and its tributaries, involves not only improving its biodiversity through planting and fish passage remediation – we also need to reduce the impact of the urban environment on stream health. This means reducing pollution in the form of litter, dog poo, toxic run-off from roads, vehicles and hard surfaces and household and industrial pollutants that are washed into the stormwater system.

Project Maitai/Mahitahi has been focussing on education and awareness, with a campaign around ‘only rain down the drain.’

In November 2016, nine schools collaborated with three Countdown supermarkets to paint messages on the drains in the supermarket carparks. The paintings are a lasting reminder that our stormwater drains lead straight to the river and Tasman Bay.

Project Maitai/Mahitahi also worked with students from the NMIT Digital Animation class to produce animations explaining why we should only let rain down the drain. One of these animations, by Elaine Ang, is now being shown at the State Cinema.

         

Only Rain Down Drain artworks by Auckland Point and Nelson Central Schools

 
Public Information

Along with bi-monthly pages in The Leader and posts on our Facebook page, Project Maitai/Mahitahi gained further visibility with the installation of window blinds in the Halifax Street Council windows which tell the story of the project so far.

Council also installed signage in the Maitai Valley highlighting short walks to help more people enjoy our lovely river valley. This information will be produced as a brochure which will be available from the customer service centre.